Data type mapping table
Written by
Updated at March 31, 2025
When you create a dataset, DataLens converts the source data to its own type for streamlined data processing.
This helps DataLens unify the operations with data from different sources.
The table below shows how data types of different databases and DataLens internal data types map.
| DataLens | ClickHouse® | PostgreSQL | MySQL | MS SQL |
|---|---|---|---|---|
| Boolean | boolean | boolean | bit | bit |
| Date | date | date | date | date |
| Date and time | datetime | timestamp | datetime timestamp |
datetime datetime2 smalldatetime datetimeoffset |
| Fractional number | float float32 float64 decimal* |
real double precision numeric |
float double numeric decimal* |
float real numeric decimal* |
| Integer | integer int8 int16 int32 int64 uint8 uint16 uint32 uint64 |
smallint integer bigint |
tinyint smallint mediumint integer bigint |
tinyint smallint integer bigint |
| String | string enum8 enum16 |
char varchar text citext |
tinyblob blob binary varbinary char varchar tinytext text enum |
char varchartext nchar nvarchar ntext |
| Geopoint | Set by a formula in DataLens | Set by a formula in DataLens | Set by a formula in DataLens | Set by a formula in DataLens |
| Geopolygon | Set by a formula in DataLens | Set by a formula in DataLens | Set by a formula in DataLens | Set by a formula in DataLens |
| Array of integers | Array(integer) Array(int8) Array(int16) Array(int32) Array(int64) Array(uint8) Array(uint16) Array(uint32) Array(uint64) |
Array(smallint) Array(integer) Array(bigint) |
Not supported | Not supported |
| Float array | Array(float32) Array(float64) |
Array(real) Array(double) Array(precision) Array(numeric) |
Not supported | Not supported |
| Array of strings | Array(string) | Array(char) Array(varchar) Array(text) |
Not supported | Not supported |
* There may be a loss of accuracy when converting data.
ClickHouse® is a registered trademark of ClickHouse, Inc.